KARL POPPER almost came to the University of Sydney in 1945. John Anderson invited him to join the staff in Philosophy but Popper delayed his decision in the hope of an offer from the London School of Economics. When that offer came he withdrew his application for Sydney and so Professor Anderson was spared the confrontation with an ego equal in size to his own.

Popper died in 1994 at the age of ninety-two, and Malachi Hacohen's Karl Popper: The Formative Years, 1902 - 1945 is the first comprehensive book to appear on his life and work. Hacohen, a historian based at Duke University, has charted the evolution of Popper's thinking with close attention to his intellectual influences and the explosive social and political tensions in Vienna which informed his thoughts on politics and ultimately prompted his flight to New Zealand. Over twenty years in the making, this is likely to be the standard reference for some time because the author had access to some recently opened archives and also interviewed some long-standing colleagues of Popper such as Colin Simkin (from New Zealand)and John Watkins (of the London School of Economics) who are no longer with us.

The book has at least four different aspects, each of considerable interest. One is the reconstruction of Popper's intellectual career as he groped towards his seminal work in the philosophy of science and politics. The second is to give some impression of Popper the person, the being of flesh and blood who is practically invisible in his intellectual autobiography Unended Quest. The third is the recreation of the social and political milieu of Vienna, the life of high culture and intellectual achievement that thrived but finally expired under the volcano of fascism and anti-Semitism. The fourth is Hacohen's mission to reclaim Popper for the social democrats, to snatch him back from the clutches of the Cold War liberals and the New Right.

So far as Popper the person is concerned, Hacohen had great difficulty in getting anywhere near the emotional roots of Popper's life. He was so much a man of ideas that everything else appeared to be secondary (after early thoughts of a career in music), including his own comfort and the convenience of anyone who had dealings with him.

Hacohen reports that Popper worked for 360 days of the year, all day, without the distraction of newspapers, radio or television. Several times a month, even in old age, he worked all night, and some friend such as Bryan Magee would get an early morning call from Popper, bubbling with excitement to report on his latest ideas. Popper lived well out of London near High Wycombe, and when Magee gained Popper's confidence he was invited to visit, taking the train to "Havercombe" (in Popper's heavily accented English).

When I made the trip to Havercombe, Popper arranged to meet me at the station, carrying a copy of the BBC Listener, presumably to pick him out from all the other elderly gentlemen of middle-European extraction who might be thronging the platform at two o'clock on a Wednesday afternoon. In the event, he left the magazine at home and the kiosk had sold out so he had to buy the Times and fold it to the size of the Listener. Of course he was the only person in sight apart from the stationmaster.

Popper, then aged seventy, had what his research assistant tactfully described as a "very positive" attitude to driving. Fortunately it was not far to his home and there were few other cars on the road. Safely home, our conversation laboured, and he frequently pushed a tray of choc-chip cookies towards me. Later he lamented to his assistant that I had eaten a whole week's supply of his favourite cookies in one afternoon. These aspects of Popper are the other face of the man who some described as "the totalitarian liberal".

Magee endorsed the view that Popper's personal behaviour often belied his liberal principles. In fairness, he added that Popper had to endure persistent and gross misrepresentation of his ideas by philosophical and political opponents. On the topic of misrepresentation, Hacohen has resoundingly corrected the rather odd view propounded by David Stove regarding the motivation for Popper's challenge to orthodoxy in the philosophy of science. Stove suggested that this was done in the frivolous spirit of the Jazz Age, so if other people wanted scientific theories to be verified, highly probable and justified, Popper would have them falsified, improbable and conjectural.

In fact it is difficult to imagine anyone more divorced from the spirit of the Jazz Age than the priggish, puritanical, non-smoking, non-drinking young Popper. Apparently his idea of a good time outside working hours was a session as a voluntary helper in Alfred Adler's social work clinic in the slums of Vienna. Following Tolstoy's ideas on the dignity of manual labour, Popper tried various jobs and he completed an apprenticeship to become a qualified cabinet maker.

Apart from a teenage flirtation with the communist movement, Popper's nearest approach to radicalism was Arnold Schoenberg's Society for Private Musical Performances, which he attended out of a sense of duty to explore contemporary music. However, when he started serious writing for publication there was no time for that kind of distraction and often on weekends Popper would sit with his wife in a coffee shop writing drafts which she typed up on a portable typewriter.

POPPER'S LACK of progress in the community of professional philosophers needs to be understood against the background of the ideas that dominated Anglo-Saxon philosophy under the influence of Wittgenstein in his two phases. It needs to be remembered that the philosophy of science was not institutionalised in the 1920s and there was only a handful of academics in that field in the world. The issues that are now addressed by some hundreds and maybe thousands of full-time staff and students around the globe were in those days the preserve of small groups of interested people, including working scientists, many of them outside the universities, like Charles Sanders Peirce and Bertrand Russell for much of their lives.

Such was the Vienna Circle of logical positivists who gathered around Professor Moritz Schlick (1882 - 1936), Rudolph Carnap (1891 - 1970) and Otto Neurath (1883 - 1945). Their spiritual predecessor was Ernst Mach (1838 - 1916) a philosopher-physicist in the strong empiricist tradition of David Hume, whose mission was to purge science of metaphysics and place it on the firm "positive" foundations of sensation. Few philosophers have had such a deep and wide-ranging influence. In Hacohen's words, "He virtually became the official philosopher of Viennese progressivism" (and far beyond) through his influence in psychology, physics (the young Einstein), literature (Robert Musil), painting (the Impressionists) and social philosophy (Joseph Popper-Lynkeus).

They pursued Mach's positivism, with Russell's Principia their inspiration and Wittgenstein's Tractatus providing the program. This was essentially a war on metaphysics by application of the strict "verificationist" definition of meaning. They proposed that statements should be regarded as literally meaningless if they could not be confirmed or verified by evidence. The propositions of logic and mathematics were exempt from the requirement for verification on the understanding that they are true by definition and they do not pretend to convey information about the world.

The most obvious casualties of the verification principle were religion and moral principles, though there were others that were less obvious, including the principle itself and, most regrettably, the laws of science. When these laws are stated in their strong (universal) form they cannot be verified by any number of observations. This dilemma, with the unsolved problem of induction, represented twin "skeletons in the cupboard" of positivism, but still the circle gained world-wide influence, and they did institutionalise the philosophy of science with a series of conferences in the 1930s with the sponsorship of luminaries such as Bertrand Russell. Then the predominantly Jewish and left-wing members of the circle had to scatter for their lives, like Popper himself, and they were dispersed far and wide by 1939.

Manning Clark recorded in his autobiography The Quest for Grace something of the flavour of encountering the crusading spirit of the positivists, round about 1940:

'The first time I sat down in the "caf" at Melbourne University I asked politely, "Would you please pass the salt?" My neighbour, a gifted woman, looked at me with the eye of the saved for the damned and said, "I don't know what you mean." I decided to listen to what was going on. In the ensuing weeks I picked up a new vocabulary. I often heard the word "tautology": that, I gathered, was a sin against the Holy Ghost. I heard the phrase "non sequitur". I was often asked: "Is that a verifiable proposition?"'

As the circle pursued their program in the 1930s two other forces loomed up on the horizon. One was an intellectual challenge from a young schoolteacher, the other was the lengthening shadow of the swastika.

Popper's career did not pursue any steady course through the 1920s. His father was ruined by the post-war inflation and Karl left home to live in a commune in an old army barracks. Decked in army surplus attire he attended courses in science and mathematics as an unmatriculated student at the university, eking out a living by coaching overseas students. (Arthur Koestler was studying engineering at the university at the time, until he departed to support Zionism in Palestine.)

There was no prospect of a career and he engaged in socialist causes and social work. His early experience as a voluntary teacher with a group called the "Young Proletarians" was not inspiring. The working-class children were resistant and greeted the young teacher with loutish behaviour. Things improved after Popper challenged the leader of the roughnecks to a boxing match.

Eventually he found a place to train as a proper schoolteacher, in a newly formed Pedagogic Institute that was established to support Glockel's school reform movement. There he learned philosophy and psychology from Karl Buhler (1879 - 1964), took on board Kant's view on the projection of intellectual categories upon the world, moved his focus from the psychology of learning to the logic of theory formation and testing, and courted and married a fellow trainee-teacher. Josefine Henninger, "Hennie" (1906 - 85) was a physical education teacher who became Popper's greatest helper.

POPPER ADDRESSED a different problem from that of meaning and metaphysics because he was concerned with the difference between science, where evidence matters, and pseudo-sciences such as astrology where theories appear to be based on observations but are actually "unsinkable". His exemplar of science was Einstein's theory, which might have been refuted by a particular set of observations on the eclipse of the sun.

Inspired by this example Popper advanced his criterion of falsifiability (testability) along with a set of conventions or "rules of the game" of science to ensure that the truth of theories can be tested by evidence. It is worth noting that testable statements are not confined to the "hard sciences" or even to the natural sciences, and Popper's "rules of the game" can be applied to investigations in any field including history and literature. As for induction, Popper proposed that science could do without it, making its way by means of speculations controlled by criticism, especially the criticism of experimental or observational tests. On this account science is not an edifice based on observational foundations, it is more like a hot air balloon that is tethered to the "earth" of facts and observations by thin deductive threads.

These ideas on demarcation and induction formed slowly as Popper conducted endless discussions and debates with members of the inner Vienna Circle (Viktor Kraft and Herbert Feigl) and others on the periphery, such as Heinrich Gomperez. It was Herbert Feigl, after a night-long session, who proposed that Popper should write a book. Hacohen provides a dramatic account of the writing, revision and publication of Logik der Forschung in 1934, one of a series of monographs produced by the Vienna Circle (it appeared in English in 1959 as The Logic of Scientific Discovery).

All manner of problems intruded, political tensions were on the rise, the inner Circle members were divided on the acceptability of the book, Popper's first effort had to be cut almost in half, the editor procrastinated for months before reading the manuscript, Popper was madly impatient to get into print and rubbed everyone up the wrong way, there were paper shortages, other books to be considered for publication in the series.

Hacohen gives a lot of credit to the logical positivists of the Vienna Circle for putting up with Popper's Steppenwolf-like activity, prowling on the fringe of the circle where Schlick, Carnap, Neurath et al huddled around their campfire, seeking warmth and consolation from the dying embers of the verification principle. They accepted Popper's book because most of them perceived that it had merit even if none of them really agreed with Popper's turn from verification and induction to a theory of conjectural knowledge that may be tested but is never confirmed or even assigned a numerical probability.

In the background to all this intellectual activity there were ebbing and flowing tides of political revolution. The communists plotted, the anticommunists reacted, the socialists took control of the Vienna city council in democratic elections, the Jewish problem created continuing tensions. Hacohen has a special interest in the Jewish problem and he may have overdone this part of the narrative, but his account of the shifting balance of power between the rival forces is engrossing.

Popper had huge admiration for many aspects of the socialists' program but he despaired of their tactics - they talked violent revolution (though their moderate leadership did not believe in it) and this prompted a violent reaction which they were not sufficiently organised and resolute to match, even when they had the numbers to prevail. Against them were arrayed the conservative bourgeoisie and much worse elements of the kind that flocked to Hitler's banner.

Eventually Hitler annexed Austria and all bets for civilisation were off. Those who could see the writing on the wall, like Popper and Ludwig Mises (Hayek's teacher), escaped if they could. Mises fled to Switzerland, just before his apartment was raided. Popper's teacher Karl Buhler was less fortunate; he was arrested and interned for some weeks until he had the chance to escape by walking over the border to attempt a new life in the United States. Later on Popper counted sixteen relatives who perished in the Holocaust.

After Logik der Forschung was launched, Popper's focus shifted to politics and the social sciences. His major concern was the failure of Marxism to provide a bastion against the rise of fascism and he attributed this more than anything to an intellectual error, namely the doctrine of historical inevitability. He labelled this "historicism" and he returned to his notes on "the poverty of historicism" in 1938 when he was settled at Canterbury College, Christchurch. By that time he was writing in English and his closest colleague was Colin Simkin, a young New Zealand economist (aged twenty-six when he met Popper).

Popper had a low opinion of the social sciences, although he thought mathematical economics had turned the corner, an opinion based on almost complete ignorance of the field. He relied heavily on the young Simkin for an introduction to the innovations of Keynes and for advice on the capacity for social engineering by democratic governments to control major problems such as monopolies and mass unemployment.

In return for this dubious assistance, he offered Simkin the advice to develop his mathematical skills in order to pursue the path of macroeconomic modelling. This advice turned out to be something of a disaster for Simkin because it seems that this lifelong project failed to bear fruit. Simkin later came to the University of Sydney to assist in the battle against the Marxists in the Department of Economics.

DESPITE ALL the pressures of the times, the loneliness and isolation of New Zealand, the dreadful news from home, the threat of the Japanese advance, Popper's teaching load and problems with his professor (described in Roger Sandall's book The Culture Cult), The Open Society and its Enemies was eventually written and dispatched. This book can be seen as a kind of "Battle of Britain" in the world of ideas, a desperate counterpart to the struggle where young men daily took to the air in the skies over the south of England with the future of civilisation virtually in their hands. On the other side of the world a relatively young Karl Popper patrolled the stratosphere of the world of ideas, confronting those from Heraclitus and Plato to the present day whose ideas he thought were undermining the cause of freedom and the open society. Like the young men in their Hurricanes and Spitfires, he did not fly in vain. The Open Society joined Hayek's The Road to Serfdom to provide twin pillars of resistance to totalitarian thinking after the war.

The Open Society and its Enemies is a monumental defence of democratic principles and a demolition of many pervasive ideas that render our traditions of rationality and tolerance dangerously fragile under the pressure of social and political crises. Chief among these is the utopian impulse to recreate society in the image of someone's dreams. There is some debate as to whether Popper's dramatic view of science as a succession of revolutions is consistent with the relative conservatism of his political philosophy. In fact there is no conflict because both garments are cut from the same cloth of critical rationalism, the spirit of criticism, respect for arguments, for the truth and for the rights of individual people.

In view of Hacohen's plea to the socialists of the world to rally behind the ideas of Popper, it is essential to work out whether Popper provides support or resistance to policies of state intervention along socialist or social democrat lines. Popper is generally regarded as a social democrat because he supported state intervention to counter monopolies and unemployment, to protect the economically weak from the economically strong. To assess the legitimacy of Hacohen's claim on Popper it is helpful to examine the impact of Hayek on Popper, and also to consider some of the implications of Popper's ideas that he never followed to their logical conclusion.

Briefly, it appears that when Popper's views are adjusted to take account of his misunderstanding of the nature of monopoly and the real causes of unemployment, his basic principles place him with minimal-state liberals or even libertarians. The important assumption here is that the mass unemployment of the 1930s was caused by injudicious state intervention (by minimum wage laws, by central banks and tariff barriers and so on), and by excessive trade union power, not by the inherent instability of free markets.

Hacohen describes Popper's correspondence from Hayek which commenced in 1943 while The Open Society was still in manuscript. Hayek's reaction was gratifying but he took fright at Popper's language of social technology and social engineering. Hayek had identified the enemy, even more than the historicist, as the constructivist rationalist (the coercive utopian) who thought he could impose a pattern upon the organisation of a whole economy, like an engineer working from a blueprint.

Popper was concerned with freedom and he was equally concerned with human suffering and deprivation, after his formative years surrounded by the abject poverty in Austria after the Great War. Like the Prince of Wales visiting the unemployed Welsh miners during the Great Depression, he knew "Something must be done!" For this reason he reserved the right of the state to intervene so that the economically powerless could not be exploited by the economically powerful. He was a free trader in goods because he recognised that under monopoly, the consumers may have to pay to cart away the rubbish produced by the monopolist. He was not a redistributionist and he was not unduly concerned about disparities of income, although he acknowledged that it was disturbing to see extremes of wealth.

What was to be done about mass unemployment, the major cause of widespread suffering (apart from war)? This was never specified, though he would have learned the dangers of state interference with the labour market if he had read the works of E. H. (Bill) Hutt on collective bargaining and the strike threat or (some time later) The Case Against the Arbitration Commission by P. P. McGuinness. Popper came near to a breakthrough in economics in the course of appraising Marx on capitalism and the "excessive" labour supply that supposedly leads to exploitation. He wrote in Chapter 20 of The Open Society:

'What is not so clear, and not explained by Marx either, is why the supply of labour should continue to exceed the demand. For if it is so profitable to "exploit" labour, how is it, then, that the capitalists are not forced, by competition, to try to raise their profits by employing more labour? In other words, why do they not compete against each other in the labour market, thereby raising the wages ... It appears that the phenomena of "exploitation" which Marx observed were due, not, as he believed, to the mechanism of a perfectly competitive market, but to other factors - especially to a mixture of low productivity and imperfectly competitive markets.'

Low productivity and imperfectly competitive markets! These are recognised by free traders as a consequence of inappropriate and counterproductive government intervention. Interference with the labour market has been particularly damaging and it appears that the immediate cause of mass unemployment in Australia during the Great Depression was the fact that award wages were only reduced by 10 per cent at a time when prices had fallen by much more than that figure. One of the best-kept secrets of modern history is the comfortable situation of the people who remained employed for the duration at 90 per cent of the previous wage rate while tens of thousands had no regular income at all. This secret was leaked, not by a historian or a sociologist or even by an economist but by the novelist Jessica Anderson in Tirra Lirra by the River.

As a result of Hayek's influence Popper emphasised that state intervention should take the form of laying down clearly formulated rules, and state officials should not be empowered to issue discretionary orders to achieve particular short-term aims. He became more alert to the dangers of increasing state power, he insisted that social democratic policies should never be envisaged as a "cure-all", and he warned that socialists of goodwill should be alert to abuses of power that could result from increased state activity, however well meaning the original intention might be. In March 1944 he wrote to Hayek, "I think I have learnt more from you than from any other living thinker, except perhaps Alfred Tarski."

The result of all this is distressing to Hacohen:

In the postwar years, Popper no longer demonstrated commitment to reform ... He never disavowed piecemeal engineering, but he argued that its purpose was to decrease, not increase, state power. He also showed growing sympathy towards libertarianism, and did little to stop the conservative onslaught of the 1980s.

Hacohen cited a reference to a 1982 interview where Popper expressed some sympathy with anarchism: "It was, he said, an unrealisable ideal but the closest we can get to it, the better off freedom is."

Hacohen's statement above seems to assume that decreasing state power does not count as reform. Such is the gulf that has opened up between socialism and common sense. Hacohen hopes that the left can be reinvigorated by Popper's ideas, properly understood, to regain their sense of mission, to recover from the setbacks of the Thatcher and Reagan years, take the offensive and move forward again. I have a similar hope, that the left can move forward, but in a very different direction, the direction of classical liberalism, the direction pointed by Mises and Hayek, and by Popper in his stance as a minimal-state liberal.

Despite this negative conclusion regarding one of Hacohen's aims I do not want to leave the reader with an unfavourable impression of the book. It is a work of quite remarkable scholarship, well organised, clearly and vigorously written. It will provoke debate among friends of Popper's ideas, and perhaps among others who are less friendly. It should lead to a reconsideration of Popper's low standing in contemporary philosophy. It stands as a monument to Popper's indomitable spirit and to the support of many people, not all of them adequately recognised by Popper himself, who helped him on his way. These include some members of the Vienna Circle, Karl Buhler, Robert Lammer (the diligent first reader of Logik der Forschung), Ernst Gombrich and Colin Simkin. May they never be forgotten.

Rafe Champion writes: I would like to dedicate this article to the memory of Keith Barley, Reader in

Agronomy at the Waite Agricultural Research Institute, Adelaide, who lent me The Open Society